To date much work has been done in the desalination area. For example, WO9735125 purports to improve the end-closures of the pressure vessels. Efforts were devoted to protect pressure vessels with side ports: e.g. EP1335162. For example, WO2013080623 purports to provide improved pressure vessels with side ports, however, the pressure tubes are specially designed to withstand the ellipsoidal strains.
WO2005105274 discloses an assembly of pressure vessels with side ports, this disclosure purports to provide for the protection of an assembly of several pressure vessels; wherein the pressure vessels have the characteristic of being supplied with raw water in the middle position, in contrast to conventional pressure vessels which are fed at one end opening or the other.
WO2011149626 purports to reduce clogging problems due to precipitation of dissolved solids within cylindrical filtration cartridges. To design pressure vessels that can be supplied with raw water at one end, and at the same time at the center of the tubes. Thus the concentration of the cross-membrane concentrate, which is the feed liquid of the next membrane, is sharply reduced, which reduces the risk of clogging by precipitation of dissolved solids, and which also reduces the feed pressure.
WO2012006362 purports to reduce the number of components, and thus the pressure vessels, while installing the same number of cylindrical filtration cartridges. The difference of this patent with our invention is that the use of pressure vessels is kept. Although vessels are larger, and are equivalent to 7 current pressure vessels, these tubes retain all the characteristics of the current reverse osmosis racks: the tubes are independent of each other, they are mounted on a steel structure, and require stainless steel piping to connect to each other. Furthermore, this patent has also a special feature at the first claim: each membrane of the same series in the same pressure tube is fed with raw water, in order to reduce the concentration of the inlet fluid on the latest cylindrical filtration cartridges.